Shielded electrode tube



March 17; 1936.

R. M. 'HEINTZ SHIELDED ELECTRODE TUBE Filed Sept. 6, 1933 2 Sheets-Sheet l L lmlrlllllfllllllm INVENTORY RALPH M. HIN rz.

A TTORNE Y March 17; 1936.

R. M. HEINTZ SHIELDED ELECTRODE TUBE Filed Sept. 6, 1933 '2 Sheets-Sheet 2 INVENTOR. RALPH M. HE/NTZ.

ATTORNEY Patented Mar. 17, 1936 UNITED STATES.

PATENT OFFICE 2,034,433 v v snmmnn ELECTRODE TUBE RalphM. nemu. Palo Alto, cum, assi ito Heintz d: Kant Ltd., a corporation of Nevada Application September 6, 1933, Serial No.

San Francisco, Calif.,

8 Claims. (01. 250 -36) My invention relates to a thermionic tube and more particularly to tion herein described, adopted within the scope of the claims.

Referring to the drawings which illustrate several embodiments of my invention, all somewhat diagrammatically represented for the sake of clearness:

Figure 1 view 01' an example and anode, and inserting the The filamentary cathode bein 'a cross sectional view taken as indiconnected up g grounded,

of a com ition to which glass The grid is preferably of circular shape and is provided with a central aperture 2 crossed by As the envelope portions are connected by the central aperture 2, the combined envelopes may be considered as a single tube envelope, the grid electrode passing through its walls.

An anode I0 is portion on an anode lead ll sealed througlrthe The anode and cathode are thus completely separated electrode.

The grid electrode may then be continued l 2 away from the tube by the use of an exterior shield l5 which is provided with an envelope aperture IS. The tube is inserted in this aperture, which is preferably larger than the envelope but smaller than the gridfiange 9, the tube being supported by fastening the grid flange to the shield by screws l1, the positioning being preferably concentric so that no openings anode tuned circuit comprising the anode inductance l9 and anode variable capacity is grid. The electron connected in series with an anode source 2! to the anode, the other end of the anode source going to a common anode-cathode point 22,

grounded for radio frequency through condenser 23. The anode source is also preferably shunted by a by-pass capacity 24.

As the cathode l2 requires two leads for con-' ducting current thereto, it is desirable to include both leads in a cathode-tuned circuit. This may be done in several ways. all well known in the art, but I prefer to make one lead a hollow conductor 25 wound into an inductance, the other lead 26 being run through the tube. The hollow conductor 25 and inner lead 26 are then connected to a cathode source 21, the ends of the hollow conductor being shunted by a cathode variable capacity 29 to complete the cathodetuned circuit. The hollow conductor side of the cathode source is then connected to the common anode cathode point 22.

The circuit thus formed will cause the tube to oscillate, having cathode circuits, behaving in much the same manner as the well known tuned-grid tunedplate circuit, in which the coupling between the two circuits is the anode-grid capacity. In this case the coupling is the anode-cathode capacity.

The tube and circuit described, however, differ from the ordinary tuned-grid tuned-plate combination in that in this example the two fluctuating electrodes are separated by the grounded stream, however, is under complete control as the grid is in its usual position for proper control. Furthermore, as control is increased, as by making the grid wires liner and closer together, the shielding becomes better and reaches the point where it is virtually complete.

The tube as above described in combination with the related circ ts will oscillate freely and supply substantial amounts of power of high frequencies at which the usual tube and associated circuits fail.

The remaining figures, 3, 4, 5, and 6 show various embodiments of the invention.

In Figure 3, the envelope is provided with an expanded portion 30 in which the grid electrode is positioned. The exterior shield l5 has attached thereto a pair of cooperating flange rings 3!, the

inner portions of which are shaped to enclose the expanded portion and thus overlap the periphery of the grid electrode. The internal and exterior portions are then connected through a grid'seal 32.

In Figure 4 the anode end of the envelope is somewhat expanded and of larger diameter than the cathode end. A shoulder 33 thus may be used to position the tube in the envelope aperture,

' shield I positioned so parallel tuned-anode tuned- In Figure 5, the grid electrode fits the envelope and is formed with a peripheral flange 34 which extends parallel to the envelope. The-exterior i5 is provided with a flange ring 35 on which an exterior flange is turn The tube is that the two flanges are opposite and the grid connected to the shield through the grid seal 32.

The embodiment shown in Figure 6 is practically identical with'that shown in Figure 1, except that in this example the grid control portion and the anode are concentric cylinders,

grid control wires I being supported by a tube 36 extending from the body of the grid electrode which is sealed through the envelope walls as shown in Figure 1. The catho'de leads pass along this tube, and the grid wires are provided with a top cap 31 to complete the shielding.

While the shielding provided by the embodiment shown in Figures 1 and 6 might seem to be better than the shielding provided in the remaining embodiments, the leakage space is only that provided by the thickness of the envelope wall which is usually quite thin. The examples shown wherein the grid electrode is not sealed through the wall are cheaper to manufacture, and tubes using this construction will oscillate at frequencies well below those obtained by ordinary tubes. However, the complete shield formed by extending the shield through the envelope walls is to be preferred where a slight increase in cost is no deterrent in obtaining the most efficient production of oscillating power.

It should also be noted that when the grid electrode is sealed through the walls, the tube may be mounted on the panel or shield by the direct fastening of the exterior portion to the panel, thus obviating a base of any kind, as connections from the associated circuits can be made to the leads of the remaining electrodes on the proper side of the shield.

I claim:

1. In combination with an electrostatic shield for separating a pair of tuned circuits, a thermionic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said control electrode forming a continuing portion of said shield.

2. In combination with an electrostatic shield for separating a pair of tuned circuits, a thermionic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said control'electrode passing through the wall of said envelope to form a continuing portion .of said shield.

3. In combination with an electrostatic shield for separating a pair of tuned circuits, a thermionic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said control elect-rode havinga central perforate portion and a peripheral imperforate portion, said imperforate portion being extended through the walls of said envelope to form a continuation of said shield.

electrostatic shield for separating a pair of tuned circuits, 9. thermionic tube comprising an envelope containing an 7 anode, a cathode, and a control electrode positioned between said anode and cathode, said control electrode forming a continuing portion of said shield, one of said tuned circuits being connected to said anode and the other to said cathode.

5. In combination with an electrostatic shield for separating a pair of tuned circuits, a thermiic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said conshield, one of said tuned circuits being connected to said anode and the other to said cathode.

6. In combination with an electrostatic shield for separating a pair of tuned circuits, a thermionic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said control electrode having a central perforate portion and a peripheral imperforate portion, said imperforate portion being extended through the portion of said shield, being connected to said anode and the other to walls 01' said envelope to form a continuation of said shield, one of said tuned circuits being connected to said anode and the other to said cathode.

7. In combination with a g:ounded electrostatic shield for separating a pair of tuned circuits, a thermionic tube comprising an envelope containing an anode, a cathode, and a control electrode positioned between said anode and cathode, said control electrode forming a continuing one of said tuned circuits said cathode.

8. In combination, a pair of tuned circuits, an electrostatic shield positioned to prevent coupling between said circuits, said shield having an aperture therein, anda thermionic tube having an envelope containing an anode, a cathode and a grid therebetween, said grid being peripherally extended through said envelope to close said aperture, one or said circuits being connected to said anode, the other to said cathode.

RALPH M. HEINTZ. 

